The present invention relates to a silver halide photographic light-sensitive material, and more particularly to a silver halide photographic light-sensitive material having improved graininess and excellent sharpness.
In recent years, there has been remarkable technological progress for increasing the speed of as well as for improving the image quality of silver halide photographic light-sensitive materials, particularly silver halide color photographic light-sensitive materials. That is, to meet the need for increasing the speed, improvements have been made by providing two or more emulsion layers differing in the speed but having sensitivity to the same spectral region and by the use of two-equivalent-type couplers, while for improving the image quality, the development and use of DIR compounds have played an important role.
Particularly, the above-mentioned DIR compound for use in the improvement on the image quality, i.e., the graininess and sharpness, by its coupling reaction with the oxidized product of a color developing agent, releases imagewise a development inhibitor to thereby inhibit the silver development to prevent possible enormous growth of dye cloud, and concurrently carries out gradation control, thus resulting in the increase in color forming points to improve the graininess. At the same time, the imagewise produced development inhibitor diffuses to thereby further strengthen the edge effect, thus also improving the sharpness.
However, color photographic light-sensitive materials for amateur use in recent years show a marked tendency to become increasingly smaller in the film format for ease of handling, simplification of the processing, or for the purpose of silver saving. This tendency naturally leads to the need for a larger magnification of a negative film to make enlarged photographic prints, so that a further improvement of the graininess, particularly of the graininess in a low exposure scale is desired.
In ordinary silver halide color photographic light-sensitive materials, in general the lower the exposure scale, the less do the color forming points become, so that the graininess becomes worse. In the present situation where the provision of a plurality of emulsion layers sensitive to the same spectral region but differing in the speed is most popularized, even if an attempt is made to increase color forming points by minimizing the silver halide particle size of a high-speed emulsion layer, there would be naturally a limit to the attempt in respect of the speed.
In contrast to this, a method for improving the graininess by use of a nondiffusible coupler capable of producing a movable dye is recently disclosed in Japanese Patent Publication Open to Public Inspection (hereinafter referred to as Japanese Patent O.P.I. Publication) No. 82837/1982. The technique in this method, as described in the publication, shows an improving effect upon the graininess but does not come up to the improvement on the sharpness. The above technique is therefore desirable to be utilized in a layer for producing an yellow dye, to which color the naked eye is less sensitive, so that the technique lacks the actual improvement effect on the graininess of a photographic image that is easily distinguishable by the naked eye.
It is therefore an object of the present invention to provide a silver halide photographic light-sensitive material which is capable of making up for the above disadvantages, and of forming a photographic image excellent not only in the graininess but also in the sharpness.